1. Field of the Invention
The invention relates to flash memory, and more particularly to a data storing method and apparatus for multi-level cell (MLC) flash memories.
2. Description of the Related Art
Non-volatile memory, such as a NAND flash memory, which has the advantages of a speedy programming time, a small chip area and low power consumption, commonly serve as storage media for various kinds of multimedia data, e.g., secure digital (SD) cards or compact flash (CF) cards.
In general, a NAND flash memory may comprise a single-level cell (SLC) flash memory and a multi-level cell (MLC) flash memory, wherein each single-level cell may store two values ‘0’ and ‘1’ and each multi-level cell may store four values, such as ‘00’, ‘01’, ‘10’ and ‘11’, thus allowing for higher storage density. However, compared with the single-level cell flash memory, the multi-level cell flash memory disadvantageously involves a low data transfer rate and is subject to data corruption and data loss.
Therefore, it is desirable to provide a data storing method capable of solving the problems due to data loss induced by the multi-level cell flash memory and further improving the reliability of data retention.